Locks



Oct. 30, 1962 F. .1. BUTTER Locxs Filed May 25, 1960 5 Sheets-Sheet 1 Ahorney Get. 30, 1962 F. J. BUTTER 3,069,716

LOCKS Filed May 25, 1960 3 Sheets-Sheet 2 A Home y F. J. BUTTER Oct. 30,1962 LOCKS 3 Sheets-Sheet 3 Filed May 25, 1960 Attorney 3,060,716 LOCKSFrancis J. Butter, Finchfield, Wolverhampton, England, assignor toJosiah Parkes & Sons Limited, Willenhall, England Filed May 23, 196i),Ser. No. 30,995 Claims priority, application Great Britain June 2, 19597 Claims. (Cl. 70-134) This invention relates to locks of the type inwhich pivoted security levers require to be lifted by respective correctamounts in order to release the bolt for direct or indirect operation bythe key. In this type of lever lock, the correct lifting of the securitylevers in order to release the bolt for operation is usually effected bycorresponding steps of respectively appropriate radial dimensions on thekey bit, which steps co-operate directly with the security lever underedges or bellies which are shaped to suit the radial dimensions of therespective key steps so as to ensure that each security lever will belifted the correct amount, whether the key is turned clockwise oranticlockwise.

The above-described usual arrangement of lever lock is generallysatisfactory where it is required to be operated always by the same key,or by one or other of a number of identically similar keys, but this isnot so satisfactory in a lock which requires to be operated by either oftwo keys which are not identically similar, for example by a servant keyand also by a master key. In the latter connection, any particularsecurity lever with its under edge or belly shaped to suit one of thetwo different keys will not suit the other key and will be lifted eithertoo much or too little by said other key in one of its turningdirections. For this reason key-operated sliders or so-called slidinglevers, instead of pivoted security levers, have been resorted to forreleasing the bolt in cases where operation by different keys isrequired, since the lift imparted to a slider by any particular key isthe same irrespective of the direction in which said key is turned; thedisadvantage, however, of using sliders is that they are lifted bodilyor as a whole by amounts corresponding only to the respective key stepsby which they are operated, whereas the advantage of using pivotedsecurity levers is that they have a lift-magnification factor, that isto say, that end of a lever which is remote from the pivot moves througha longer are than does that portion of the lever which is engaged by thekey step, and this affords more scope for notching or otherwise formingthe remote end of the lever for co-operation with a blocking element,such as an abutment or stump on the bolt, or on its runner, if any, oron a bolt-dogging lever, to suit different lifts imparted by differentkeys.

According to the present invention, a lock of the type referred to ischaracterised in that the pivoted security levers are lifted bykey-operated members, one for each lever, which members are constrainedor guided by substantially rectilinear movement and each of which whenoperated by a step of any particular key imparts the same lift to itsassociated lever irrespective of the direction in which that key isturned. Thus the advantage of pivoted security levers, due to theirlift-magnification factor, is retained and the disadvantages, hithertoassociated with such levers when required to be directly operated bydifferent keys, are avoided by the constrained or guided key-operatedlifting members which ensure that with any particular key each leverwill be lifted the same amount no matter in which direction said key isturned. In this way, the invention provides a security system which iseminently suitable for locks of a master-keyed set or suite. 4

It will, of course, be appreciated that the under edges Bfibbfi'lbPatented Oct. 30, 1962 or bellies of the key-operated lifting membersmay be of arcuate shapes for co-operation with the respective steps ofthe key or keys, although in this connection it will usually besatisfactory to make the said lifting members all alike or identicallysimilar with their under edges or bellies shaped to an are having theradius of the longest key step used.

The invention will now be described with reference to and by the aid ofthe accompanying drawings in which:

FIG. 1 is a fragmentary sectional side elevation of a lock mechanismembodying principles of the present invention, and

FIGS. 2-9 inclusive are similar to FIG. 1 and illustrate modificationsof the invention.

For the sake of clarity only one of the pivoted security levers and itsassociated key-operated lifting member is shown in each figure; also in.each figure the bolt is in the locking position with the parts of theassociated security mechanism in the positions they assume when thelocking turn of the key has been completed to enable the key to bewithdrawn from the keyhole.

Referring to FIG. 1 of the drawings, 10 is the lock casing; 11 is thebolt head which is guided in the usual opening in the forend of saidlock casing 10; 12 is the bolt lath or tail; 13 is a lanket hole in thebolt lath 12; 14 is a guide stump fixed in the lock casing 10 andengaged with said lanket hole 13; 15 is the usual key notch or talon inthe under edge of the bolt lath 12; 16 is the keyhole in the lock casing10,17 is the pivotally mounted security lever; 18 is a fixed stump uponwhich the security lever 17 is mounted, and 19 is the key operablemember for lifting the security lever 17.

The member 19 is a plate with an approximately triangular portion havinga vertical slot 20, engaged with the guide stump 14-, and a forwardportion having a vertical slot 21 engaged with a guide stump 22 fixed inthe lock casing 10 at a position forwardly of the keyhole 16 and belowthe bolt lath 12. The triangular portion of the member 19 has a partcircular or radiussed apex which engages in a complementary bearingrecess 23 in the underside or belly of the lever 17 at a point betweenits ends, said recess having side clearances, or being of a wide angle,suflicient to accommodate angular movement of the lever 17 relatively tosaid lifting member 19 during operation, whilst the under edge or bellyof the lifting member 19 is formed to an arcuate shape at 24 forco-operation with the appropriate step of either of two keys, forexample a servant key and a master key.

In the latter connection, the security lever 17 has formed in itsarcuate forward edge two notches 25, 26 and this edge of the lever isclosely confronted by a rearwardly directed toe 27 on a depending arm ofa bellcrank dogging lever 28 which is pivoted at 29 and has a rearwardlydirected arm with an abutment 30 for cooperation with a cam-likeprotuberance 31 on the upper edge of the bolt lath 12.

The security lever 17 and the dogging lever 28 are loaded downwardlytoward the positions shown by strip springs 32, 33 respectively.

The arrangement is such that, with the parts in the positions shown, thebolt cannot be pushed in because neither of the notches 25, 26 is inregister with the toe 27 of the dogging lever 23 and consequently thelatter cannot be rocked sufiiciently to clear its abutment 30 from thepath of the cam 31 on the bolt lath 12. If, however, the correct servantkey is used and turned in the bolt withdrawing direction, the member 19,which is guided for rectilinear movement at right angles to the boltmovement by the pins 14, 22 engaged with the vertical slots 20, 21respectively, is lifted directly by the appropriate key step and, inturn, lifts the security lever ter key is similar to that with theservant key except that the lift is sufficiently greater to cause thenotch 26 to co-operate with or receive the toe 27 of the dogging lever28 in order to permit bolt withdrawal.

In the remaining figures of the drawings, the same reference numbers, asused in FIG. 1, are employed to indicate like or analogous parts.

Referring now'to the embodiment shown in FIG. 2, the key-actuatedmember19 has its vertical slot 20 slidably engaged not only with the stump 14but also with arfixed' stump 34 vertically above it and the upper edgeof the bolt lath 12, whilst said member 19 has a rear portion; 35 with apart circular or radiussed upper edge which engages'the under'edge of aforwardly extending arm 36- on, the security lever 17, the main portionor body of which is'inclined so that its arcuate notched end edge ispresented to a downwardly presented toe 27 of a dogging lever 28 withaligned arms. The rear end of the bolt lath 12 is slotted to clear thepivot stump 18 and the operation is generally similar to that describedwith reference to FIG. 1.

Referring to FIG. 3, the embodiment shown is similar to FIG. 1 exceptfor the inverted arrangement of the dogging mechanism and the fact thatthe member 19, which is vertically guided as in FIG. 2, operates upon arearwardly extending arm 36 on the security lever 17 so that 'theforward end of the latter moves down as the said arm 36 is raised by thekey-actuated lifting member 19.

A more complicated embodiment is shown in FIG. 4 in which the securitylever 17 is mounted on a pivot stump 18 below the bolt lath 12 and has arearward arm 36 which is operated upon by the key-actuated liftingmember 19. The said member 19 has its longitudinal slot 20slidablyengaged by stumps 37, 33 which guide it for rectilinear movement in adirection which is radial to the axis of key rotation in the keyhole 19but is inclined upwardlyand rearwardly from the vertical, whilst thetalon 15, instead of being formed in the bolt lath 12, is formed in thelower end of a double-armed transfer lever 39 which is pivoted on thestump 37 and is arcuately slotted at 40 to clear the stump 38, the upperend of said key-actuated transfer lever 39 being engaged with a notch at41 in the bolt lath 12.

In the embodiment illustrated in FIG. the bolt lath 12 has a rectangularsection stump 42 which engages the end pockets of a conventional Hgating in the secu rity lever 17 so as to retain it in either of itsextreme positions except when the said lever 17 is lifted by thecorrect. key so that the'gating will allow the passage of the stump "42fromv one end pocket to the other as the bolt is operated by the boltstep of the said key. The ra diussed upper end of the member 19 makes anoperative pivotal connection with a complementary bearing recess 23 inthe under-edge of the security lever 17, and this pivotal connectioncombines with guide stump 14 to constrain or guide the member 19 to movein a line which is nearly radial to the rotational axis of the key inthe keyhole 16, so that said member 19 when actuated by the key willrock only slightly.

The FIG. 6 embodiment is similar to FIG. 5 except that the arcuateforward edge of the security lever 17 is notched for co-operation with adogging lever (not shown) and the pivotal connection between thesecurity lever 17 and the key-actuated lifting member 19 issubstantially vertically over the guide stump 14 and the keyhole 16 sothat said member 19, though not positively restrainedor guided for trulyrectilinear movement will deviate or rock therefrom only very slightlywhen actuated by the key.

In the embodiment illustrated in FIG. 7 the bolt is guided for verticalmovement and is operated through a bell-crank 42 by a horizontallydisposed runner 43 having a lanket hole 44 slidably engaged with thestump 18 upon which the security lever 17 is pivoted. The keyoperatedlifting member 19 is guided for vertical move ment between cheeks 45afforded by opposite limbs of a U-shaped fence around the keyhole 16;the operative connection between the said member 19 and the securitylever .17 is similar to that shown in FIG. 5, but the security lever 17,instead of being gated for co-operation with a bolt stump, has itsarcuate forward edge notched for co-operation with a dogging lever 28similar to that shown in FIG. 4 and operated by the co-operation of itsabutment 30 with the protuberance 31 on the runner 43.

The FIG. 8 embodiment has its key-actuated lifting member 19 guided uponthestump 14 and between fixed vertical cheek 45, and the operativehearing or connection between said member 19 and the security lever 17is similar to that shown in FIG. 1. The dogging lever for co-operationwith the notches 25, 26 in the security lever 17 is not shown.

In FIG. 9 the security lever 17 and the manner in which it is engaged bythe key-actuated lifting member 19 is similar to that shown in FIG. 8,but the said member 19 is formed with a vertically slotted rearwardextension the slot in which is slidably engaged with a fixed verticalguide cheek 45. vHere again, the dogging lever for co-operation with thesecurity lever notches 25, 26 is not shown.

Obviously any of the dogging lever arrangements shown in FIGS. 1, 3, 4and 7 could be adopted for any of the'embodiments illustrated in FIGS.'6, 8 and 9.

Having fully described my invention, what I claim and desire to secureby Letters Patent is:

l. A lock of the type referred to comprising a casing, a bolt slidablymounted in the casing and movable from a locked to an unlocked position,means including a plurality of security levers pivotally mounted in thecasing normally positioned to prevent movement of the bolt from saidlocked to said unlocked position, and means for moving said levers to aposition allowing movement of the bolt to the unlocked positioncomprising a plurality of key-operated lifting members, one for eachlever, said members being mounted in the casing for substantiallyrectilinear movement therein and each of which when operated'by a stepof any particular key imparts the same lift to its associated leverirrespective of the direction in which the key is turned.

' 2. A' lock as set forthin claim 1 wherein each security lever hasafree bearing engagement with the associated key-operated liftingmember.

3-. A lock as set forthin claim 1 wherein each keyoperated liftingmember is provided with an upper partly circular portion engaging. acomplementary bearing recess formed in the lower edge of the associatedsecurity lever, each recess being provided with side clearances toaccommodate angular movements of the levers relatively to said liftingmembers.

4. A lockv as set forth in claim 1 wherein each keyoperated liftingmember is provided with a slot receiving a stump fixed in the casing forensuring rectilinear movement of the member.

5. A lock as set forth in claim 1 wherein each key-operated liftingmember is provided with a slot receiving a pair of spaced stumps fixedin the casing for ensuring rectilinear movement of the member.

6. A lock as set forth in claim 1 wherein each key-operated liftingmember is guided for rectilinear movement by at least oneguide cheekfixed in said casing.

' 7. A lock as set forth in claim 2 wherein each security lever ispivotally mounted at one end in said casing and said free bearingengagement between each lever and its associated key-operated liftingmember is'positioned between the pivoted end of the lever and the freeend there- References Cited in the file of this patent 6 FOREIGN PATENTSFrance June 2, 1954 Germany Mar. 3, 1888 Italy Mar. 14, 1928 Italy Apr.14, 1931

